You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@cassandra.apache.org by Theo Hultberg <th...@iconara.net> on 2014/02/24 20:52:02 UTC
How should clients handle the user defined types in 2.1?
(I posted this on the client-dev list the other day, but that list seems
dead so I'm cross posting, sorry if it's the wrong thing to do)
Hi,
Is there any documentation on how CQL clients should handle the new user
defined types coming in 2.1? There's nothing in the protocol specification
on how to handle custom types as far as I can see.
For example, I tried creating the "address" type from the description of
CASSANDRA-5590, and this is how its metadata looks (the metadata for a
query contains a column with a custom type and this is the description of
it):
org.apache.cassandra.db.marshal.UserType(user_defined_types,61646472657373,737472656574:org.apache.cassandra.db.marshal.UTF8Type,63697479:org.apache.cassandra.db.marshal.UTF8Type,7a69705f636f6465:org.apache.cassandra.db.marshal.Int32Type,70686f6e6573:org.apache.cassandra.db.marshal.SetType(org.apache.cassandra.db.marshal.UTF8Type))
Is the client supposed to parse that description, and in that case how? I
could probably figure it out but it would be great if someone could point
me to the right docs.
yours,
Theo (author of cql-rb, the Ruby driver)
Re: How should clients handle the user defined types in 2.1?
Posted by Michael Dykman <md...@gmail.com>.
Please do. I too am working at a driver implementation and would be
delighted to be spared the research.
On Feb 25, 2014 11:29 AM, "Theo Hultberg" <th...@iconara.net> wrote:
> thanks for the high level description of the format, I'll see if I can
> make a stab at implementing support for custom types now.
>
> and maybe I should take all of the reverse engineering I've done of the
> type encoding and decoding and send a pull request for the protocol spec,
> or write an appendix.
>
> T#
>
>
> On Tue, Feb 25, 2014 at 12:10 PM, Sylvain Lebresne <sy...@datastax.com>wrote:
>
>>
>>> Is there any documentation on how CQL clients should handle the new user
>>> defined types coming in 2.1? There's nothing in the protocol specification
>>> on how to handle custom types as far as I can see.
>>>
>>
>> Can't say there is much documentation so far for that. As for the spec,
>> it was written in a time where user defined types didn't existed and so as
>> far as the protocol is concerned so far, user defined types are handled by
>> the protocol as a "custom type", i.e the full internal class is returned.
>> And so ...
>>
>>
>>>
>>> For example, I tried creating the "address" type from the description of
>>> CASSANDRA-5590, and this is how its metadata looks (the metadata for a
>>> query contains a column with a custom type and this is the description of
>>> it):
>>>
>>>
>>> org.apache.cassandra.db.marshal.UserType(user_defined_types,61646472657373,737472656574:org.apache.cassandra.db.marshal.UTF8Type,63697479:org.apache.cassandra.db.marshal.UTF8Type,7a69705f636f6465:org.apache.cassandra.db.marshal.Int32Type,70686f6e6573:org.apache.cassandra.db.marshal.SetType(org.apache.cassandra.db.marshal.UTF8Type))
>>>
>>> Is the client supposed to parse that description, and in that case how?
>>>
>>
>> ... yes, for now you're supposed to parse that description. Which is not
>> really much documented outside of looking up the Cassandra code, but I can
>> tell you that the first parameter of the UserType is the keyspace name the
>> type has been defined in, the second is the type name hex encoded, and the
>> rest is list of fields and their type. Each field name is hex encoded and
>> separated from it's type by ':'. And that's about it.
>>
>> We will introduce much shorted definitions in the next iteration of the
>> native protocol, but it's yet unclear when that will happen.
>>
>> --
>> Sylvain
>>
>>
>>
>
Re: How should clients handle the user defined types in 2.1?
Posted by Theo Hultberg <th...@iconara.net>.
thanks for the high level description of the format, I'll see if I can make
a stab at implementing support for custom types now.
and maybe I should take all of the reverse engineering I've done of the
type encoding and decoding and send a pull request for the protocol spec,
or write an appendix.
T#
On Tue, Feb 25, 2014 at 12:10 PM, Sylvain Lebresne <sy...@datastax.com>wrote:
>
>> Is there any documentation on how CQL clients should handle the new user
>> defined types coming in 2.1? There's nothing in the protocol specification
>> on how to handle custom types as far as I can see.
>>
>
> Can't say there is much documentation so far for that. As for the spec, it
> was written in a time where user defined types didn't existed and so as far
> as the protocol is concerned so far, user defined types are handled by the
> protocol as a "custom type", i.e the full internal class is returned. And
> so ...
>
>
>>
>> For example, I tried creating the "address" type from the description of
>> CASSANDRA-5590, and this is how its metadata looks (the metadata for a
>> query contains a column with a custom type and this is the description of
>> it):
>>
>>
>> org.apache.cassandra.db.marshal.UserType(user_defined_types,61646472657373,737472656574:org.apache.cassandra.db.marshal.UTF8Type,63697479:org.apache.cassandra.db.marshal.UTF8Type,7a69705f636f6465:org.apache.cassandra.db.marshal.Int32Type,70686f6e6573:org.apache.cassandra.db.marshal.SetType(org.apache.cassandra.db.marshal.UTF8Type))
>>
>> Is the client supposed to parse that description, and in that case how?
>>
>
> ... yes, for now you're supposed to parse that description. Which is not
> really much documented outside of looking up the Cassandra code, but I can
> tell you that the first parameter of the UserType is the keyspace name the
> type has been defined in, the second is the type name hex encoded, and the
> rest is list of fields and their type. Each field name is hex encoded and
> separated from it's type by ':'. And that's about it.
>
> We will introduce much shorted definitions in the next iteration of the
> native protocol, but it's yet unclear when that will happen.
>
> --
> Sylvain
>
>
>
Re: How should clients handle the user defined types in 2.1?
Posted by Sylvain Lebresne <sy...@datastax.com>.
>
>
> Is there any documentation on how CQL clients should handle the new user
> defined types coming in 2.1? There's nothing in the protocol specification
> on how to handle custom types as far as I can see.
>
Can't say there is much documentation so far for that. As for the spec, it
was written in a time where user defined types didn't existed and so as far
as the protocol is concerned so far, user defined types are handled by the
protocol as a "custom type", i.e the full internal class is returned. And
so ...
>
> For example, I tried creating the "address" type from the description of
> CASSANDRA-5590, and this is how its metadata looks (the metadata for a
> query contains a column with a custom type and this is the description of
> it):
>
>
> org.apache.cassandra.db.marshal.UserType(user_defined_types,61646472657373,737472656574:org.apache.cassandra.db.marshal.UTF8Type,63697479:org.apache.cassandra.db.marshal.UTF8Type,7a69705f636f6465:org.apache.cassandra.db.marshal.Int32Type,70686f6e6573:org.apache.cassandra.db.marshal.SetType(org.apache.cassandra.db.marshal.UTF8Type))
>
> Is the client supposed to parse that description, and in that case how?
>
... yes, for now you're supposed to parse that description. Which is not
really much documented outside of looking up the Cassandra code, but I can
tell you that the first parameter of the UserType is the keyspace name the
type has been defined in, the second is the type name hex encoded, and the
rest is list of fields and their type. Each field name is hex encoded and
separated from it's type by ':'. And that's about it.
We will introduce much shorted definitions in the next iteration of the
native protocol, but it's yet unclear when that will happen.
--
Sylvain
Re: How should clients handle the user defined types in 2.1?
Posted by Theo Hultberg <th...@iconara.net>.
There hasn't been any activity (apart from my question) since december, and
only sporadic activity before that, so I think it's essentially dead.
http://www.mail-archive.com/client-dev@cassandra.apache.org/
T#
On Mon, Feb 24, 2014 at 10:34 PM, Ben Hood <0x...@gmail.com> wrote:
> On Mon, Feb 24, 2014 at 7:52 PM, Theo Hultberg <th...@iconara.net> wrote:
> > (I posted this on the client-dev list the other day, but that list seems
> > dead so I'm cross posting, sorry if it's the wrong thing to do)
>
> I didn't even realize there was a list for driver implementors - is
> this used at all? Is it worth being on this list?
>
Re: How should clients handle the user defined types in 2.1?
Posted by Ben Hood <0x...@gmail.com>.
On Mon, Feb 24, 2014 at 7:52 PM, Theo Hultberg <th...@iconara.net> wrote:
> (I posted this on the client-dev list the other day, but that list seems
> dead so I'm cross posting, sorry if it's the wrong thing to do)
I didn't even realize there was a list for driver implementors - is
this used at all? Is it worth being on this list?